In order to indicate a maker's name, brand name, etc. on the surface of a sidewall portion of a tire, marks comprising alphabets, figures, symbols, etc. protrude from the surface of the sidewall portion. Such marks are conventionally structured such that the projection heights of the marks are as high as possible to enhance visibility of the marks. However, when the projection heights of the marks become high, air pockets are produced arising from bad rubber flow during molding of the marks, creating a problem of cure trouble.
In order to solve the above problem, various approaches have conventionally been devised for enhancing visibility of the marks and for remedying bad rubber flow during molding of the marks to alleviate cure trouble due to the air pockets by adequately arranging shapes of the marks formed on the sidewall portion (see patent documents 1 and 2, for example).
However, any of the approaches is not sufficient yet to realize both enhancement of visibility of the marks and prevention of cure trouble due to bad rubber flow, which are warring aspects; there is still room for improvement.
Patent Document 1: Japanese Patent Application Kokai Publication HEI 6-55915
Patent Document 2: Japanese Patent Application Kokai Publication HEI 10-67208